Improvement in boring-tools



WTNESSES i I ATTORNEY NPETERS. PHOTO LITHOGRAPHER WASHINGYON D c.

UNITED STATES PATENT OFE-IoE.

ANSEL F. TEMPLE, or MONTAGUE, MIoHreAN, ASSIGNOR o WILLIAM F. TEMPLE, JR, OF BOSTON, MASSAoHUsETTs.

IMPROVEMENT IN BORING-TOOLS.

Specification forming part of Letters Patent N 0. 222,101, dated November 25, 1879; application filed April 21, 1879. '4

To all whom it may concern:

Be it known that I, ANSEL F. TEMPLE, of Montague, in the county of Muskegon and 'State of Michigan, have invented a new and valuable Improvement in Boring-Tools; and

I do hereby declare that the following is afull, clear, and exact description of the construction and operation of the same, reference being had to the'annexed drawings, making a part of this specification, and to the letters and figures of reference marked thereon.

Figure l of the drawings is a representation of a perspective view of my improved boringtool. Fig. 2 is a side.vieuqthereof; Fig. 3 is a bottom view of the same, and Fig. 4, a transverse section thereof.

This invention has relation to boring-bits for spring curtain-rollers; and it consists inthe construction and novel arrangement upon a tubular shank of a double gage-loop cutter having a central entering-point, cutting-shoulders, and parallel inwardly-cutting branches diametrically opposite each other, terminaten gage. with the screw end of the hollow Shaft of a boring-machine. Extending from this shank is theloopform cuttingportionB, formed as follows: From diametrically-opposite sides of this tubular shanlr extend the base-cutters a, which are beveled from their cutting-edges inward to the bore of the shank. The exterior surfaces of these base-cutters are slightly raised from the cylindrical surface of the shank, so that the latter will follow freely in the aperture cut thereby. These base-cutters terminate in oblique lateral cutting-shoulders 1), extending inward and beveled downward from their cutting-edges and forming, by their inner ends, the bases and points of support of the extension or chamber-cutters c, which extend therefrom in the line of the bore parallel with each other beyond the base-cutters to the distance required, according to the depth of the chamber to be cut. ters are nearer together than the base-cutters by the depth of the conmeeting-shoulders, and the chamber cut thereby is of a certain smaller diameter than that of the bore cut by the main or base cutters and of certain depth and position, so that there is no variation, as is apt to be the case when independent bits are used to cut first the bore and then the chamber at the end thereof. These chamber-cutters are beveled inward from their cutting-edges and terminate in the downwardly-beveled cuttingshoulders d of the transverse bar 0,, from the center of which projects the entering-point h, which is obliquely arranged on the bar and concave oneach side, the bar being notched at the base of the point, as shown at it.

The entire cutting portion is in loop form, as shown, and is designed, as stated, to cut a bore, and at the end thereof a chamber of certain less diameter, of certain depth and in certain position, so that there will be no variation in large quantities ofwork, as is required in the construction of hollow spring curtainrollers and other articles. The inwardly-beveled cutters throw the chips and borings toward the bore of the shank, so that they will pass into the shaft of the boring-machine and be removed in the usual manner.

As there may be some variation in the kind of entering-point employed, I do notdesire to be confined strictly to the construction shown.

What I claimas new, and desire to secure by Letters Patent, is-

The double-gage boring-bit having a tubular shank, A, and loop-form cutting portion B, having laterahoutting-shoulders b, between the wide-gage bore cutters a, and the narrow gage-chamber c, and a central entering-point, h, substantially as specified.

In testimony that I claim the above I have hereunto subscribed my name in the presence of two witnesses.

ANSEL F. TEMPLE.

Witnesses A. Z. MASON, N. L. SEELYE.

These eXtension-cut- 

